Is Anesthetic Loss of Consciousness a Top Down or Bottom up Phenomenon. What Does the Neurologic Examination Say?.

Anesthesia; Functional Clinical Trial

— Top&Bottom  

Official title:

Is Anesthetic Loss of Consciousness a Cortical or Brainstem Phenomenon? What Does the Neurological Examination Say?

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03140982
• Other study ID #: Centro Bioetica 2016-05
• Status: Completed
• Phase: N/A
• First received: April 10, 2017
• Last updated: May 26, 2017
• Start date: June 1, 2016
• Est. completion date: December 15, 2016

Study information

• Verified date: May 2017
• Source: Universidad del Desarrollo
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Using very slow or fast propofol intravenous injection, monitored using standard American Society of Anesthesiology (ASA) standard and SEDLine EEG (Med Tech), the patient was evaluate by a neurologist every 30 sec using the FOUR coma scale.

Description:

Clinical experimental randomized study, approved by the Ethic Committee, with informed consent, included ASA I- II adults, without neurological illness and normal physical exam.

The patient randomized in two groups, rapid induction (GR) with propofol in target controlled infusion (TCI) effect site mode using the phamacokinetic (PK) model from Marsh ke0 1,21 min-1 using a calculated target of 5.4 ug/ml (loss of counsciousness EC95) and slow induction (GL) 10 mg/kg/h with calculated effect site concentrations (CeCALC) same PK model.

The same neurologist, blind to the correspondent group, evaluated all the patients every 30 sec using the coma FOUR scale until loss of counsciousness (LOC), defined as a FOUR (E0 no eyes opening response and /or M0 no motor response). At LOC the existance of brainstem reflex was evaluated (B no pupil and corneal reflex), respiratory pattern (R apnoea), CeCALC and patient state index (PSI) SEDline™ was recorded during all the examination.

After LOC in both groups we maintain in GR the initial target (5.3 ug/ml) and the LOC CeCALC during 10 min without intervention, except respiratory support if it was required.

Frontal EEG 4 channel and spectrogram from SEDline monitor was extracted for each case and posterior analysis.

Fisher exact test was used to describe primary outcome and difference between B and R for each group. The difference in time to reach LOC LOC, Ce and PSI was analysed with T- Student.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 16
• Est. completion date: December 15, 2016
• Est. primary completion date: December 15, 2016
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria: ASA 1-2 patients programmed for elective surgery, normal neurologic examination -

Exclusion Criteria: neurologic illness, receiving drugs that affect Central Nervous System during the last 48 hours

Related Conditions & MeSH terms

• Anesthesia; Functional
• Unconsciousness

Intervention

Diagnostic Test:
• FOUR coma scale and frontal espectrograpy evaluation
systematic evaluation using the validated FOUR coma scale during propofol administration

Locations

Country	Name	City	State
Chile	Clinica Alemana de Santiago	Santiago	Region Metropolitana

Sponsors (1)

Lead Sponsor	Collaborator
Universidad del Desarrollo

Country where clinical trial is conducted

Chile, 

References & Publications (3)

Brown EN, Lydic R, Schiff ND. General anesthesia, sleep, and coma. N Engl J Med. 2010 Dec 30;363(27):2638-50. doi: 10.1056/NEJMra0808281. Review. — View Citation

Mashour GA. Top-down mechanisms of anesthetic-induced unconsciousness. Front Syst Neurosci. 2014 Jun 23;8:115. doi: 10.3389/fnsys.2014.00115. eCollection 2014. Review. — View Citation

Wijdicks EF, Bamlet WR, Maramattom BV, Manno EM, McClelland RL. Validation of a new coma scale: The FOUR score. Ann Neurol. 2005 Oct;58(4):585-93. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	loss of consciousness a cortical or brainsteam phenomenon	with fast and slow induction we use the FOUR coma scale ( Ann Neurol. 2005;58(4): 585-93) to identify lost of brain stem activities.	1 year
Secondary	evaluation of the alfa band behavior after fast and slow inductions	the investigators analyze the time delay in stabilizing the frontal alfa band after fast and slow anesthesia inductions	1 year